Process for obtaining fast tints on the fiber



Patented Sept. 27, 19 32 UNITED STATES PATENT OFFICE IVIAX BOMMER AND ROBERT ENRICO POOL, OF BASEL, CAI.- INDUSTRY IN BASLE, 0F

PROCESS ,FOR OBTAINING FAST TIN'TS 'ON THEFIBER No Drawing. Application filed December 16, 1931, Serial No.:581,514, and in Switzerland Januarylfi, 1931.

In U. S. patent application Serial No. 389,324, filed August 29, 1929, it has been shown that leuco-derivatives of vat-dyestuiis react with diazo-compounds on the fiber to produce colored pigments. These pigments color the fiber fast tints which are quite different from those that are obtained with the vat-dyestufi's alone.

The further study of this reaction has led to the present invention, namely a process wherein fibers, which have been dyed with vat-dyestuffs that must in practice be vatted with the aid of hydrosulfite, are treated with diazo-conipounds.

It was found that the dyeings produced with the vat-dyestulfs enter into reaction with the diazo-conipounds.

In this manner tints are obtained which are more or less strongly difierent from the dyeings of the untreated vat-dyestufi and.

are distinguished from the latter in many cases by their intensity and enhanced fastness.

The process is applicable with very difi'erent vat-dyestuffs which in practice must be vatted with the aid of hydrosulfite; such are, for instance, the anthraquinone vat-dyestuffs, the indigoid Vat-dyestuiis and the products of sulfurization of carbazole-indophenols.

The new process is particularly valuable when the products of sulfurization of carbazole indophenols are used as the vat-dyestufi's and diazotized aminoazo-dyestulfs are used as the diazo-compounds, because in these cases there are obtained as a rule dyeings of black shade and, at the same time, of remarkable fastness.

The invention can be applied for obtaining fast tints on all fibers which can be dyed with vat-dyestuffs. For instance, cotton, wool, loaded or unloaded silk, artificial fibrous material of all kinds.

The following examples illustrate the inventionz- Ewample J A 10 per cent. dyeing of Hydron Blue R (Schultz, 7th Edition, No. 1111) is treated 8 grams per litre of .4 chloro-2-methyl-5- methoxy-4-diazo-azobenzene. The, material is thenrinsed, acidified, again rinsed, and dried. The blue dyeing passes into a deep,

fast black, particularly fast to kier boiling. The substitution of-otherdiazotized amino azo-compoun ds, for instance diazotized benzeneazo -naphthyhamine for the 4 chloro 2-methyl-5-methoxy-4-diazo-azoben Zene used in this example, produces as a'rule similar black dyeings.

Dark marine blue tints are obtainable with I the tetrazotized laminoazo-compound from 4J-a1nino-2-methyl- .5 -methoXy-4-amin0.-az obenzene and with more simple diazo-compounds, such as diazotized 2: 5-dichloraniline, 5-nitro-ortho-anisidine, meta-nitropara-toluidine, meta-chloraniline, 4-chloro ortho-nitraniline', -chloro-Z-amino-l;1-diphenyl-ether. 1 7

Instead of the Hydron Blue B there may used, for example, Hydron Blue, G (Schultz, 7th Edition, No. 1118).

Example 2 A 5 per cent. dyeing of Giba Red R (Schultz, 7th Edition, No. 1839) is treated for hour at room temperature in a bath containing an excess of sodium acetate and 8 grams nitraniline. The material is then rinsed, acidified, again rinsed, and dried. The red dyeing becomes fuller and more yellow.

If one treats in similar manner a 2.5 per cent. dyeing of Giba Red 3B (Schultz,7th Edition, No. 1354) with 4-chloro-2-methyl- 5-methoxy-4-diazo-azobenzene, the red-violet dyeing passes into an intense, pure, yellowish vbordeaux, which is characterized by a very good fastness tokier boiling.

Example 3 ed for hour at room temperature in a bath containing an excess of sodium acetate and 8 grams per litre of 4'-chloro-2-methyl- 5-methoxy-4 -diazo-azobenzene; the blue dye- The material is then ing passes into grey.

' rinsed, and dried. By

rinsed, acidified, again substituting for the diazotized aminoazodyestufi diazotized l-chloro-ortho-nitraniline, a very greenish grey is obtained.

A similar procedure may be adopted with other dyestuffs of the .anthraquinone series or of the benzanthrone, pyranthrone, anthanthrone, dibenzpyrenequinone and the like serles. r. r I V v For example; with Cibanone Gold Orange GN (Schultz, 7thEdition,No;1245) and e.- chloro-2-methyl5-methoxy-4c-diazo 'azobenzene there is a change from orange to brown.

\Vhat we claim is i v 1. Process for obtainingfast tints on the fiber, which consists in causing dyeings wh-ichhave been produced with such Vatdyestufts that must in practicebe vatted with the aid of hydrosulfite to react with diazocompounds. 2. Processfor obtaining fast tints on the fiber, which consists in causing dyeings which have been produced with anthraquinone Vat-dyestufis to react with diazo-compounds. r 5: Process for obtaining fast tints on the fiber, which consists in causing dyeings which have been produced with indigoid' vatdyestufi's to react with diam-compounds. V 4. Process for obtaining fast tints on the fiber, which consists in causing dyeingswhich have been produced with the products of sulfurization of carbaZole-indophenols to react with diazo-compounds. r 7

5; Process for obtaining fast tints on the zss fiber, which consists in causing 'dyeings which have been produced with-the products of sulfurization of carb'azole-indophenols to react with diazot-ized aminoazo dyestuffs.

In witness whereof we have hereunto V kmsigned our names this 7th day of December MAX BOMMER.

ROBERT HALLER. ENRICO POOL. 

